GA doesn't seem to be respecting search interval bounds

[lzfelix]

Hello!
Running GA optimization wtih the following parameters:

- target_fn: sphere
- n_variables: 10
- n_agents: 20
- mutation_rate = 0.2
- search_interval: [10, 20] for all variables

yields f(x*) = 0 as optimal value, which is only possible at the space origin, outside the search space. In this case, the expected optimal value should be f(x*) = (10^2)*10 = 1000.